stellaris: automatically generate and update device IDs

[openocd.git] / src / flash / nor / stellaris.c

/***************************************************************************
 *   Copyright (C) 2006 by Magnus Lundin                                   *
 *   lundin@mlu.mine.nu                                                    *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

/***************************************************************************
* STELLARIS flash is tested on LM3S811, LM3S6965, LM3s3748, more.
***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "imp.h"
#include <target/algorithm.h>
#include <target/armv7m.h>


#define DID0_VER(did0) ((did0 >> 28)&0x07)

/* STELLARIS control registers */
#define SCB_BASE        0x400FE000
#define DID0            0x000
#define DID1            0x004
#define DC0                     0x008
#define DC1                     0x010
#define DC2                     0x014
#define DC3                     0x018
#define DC4                     0x01C

#define RIS                     0x050
#define RCC                     0x060
#define PLLCFG          0x064
#define RCC2            0x070
#define NVMSTAT         0x1a0

/* "legacy" flash memory protection registers (64KB max) */
#define FMPRE           0x130
#define FMPPE           0x134

/* new flash memory protection registers (for more than 64KB) */
#define FMPRE0          0x200           /* PRE1 = PRE0 + 4, etc */
#define FMPPE0          0x400           /* PPE1 = PPE0 + 4, etc */

#define USECRL          0x140

#define FLASH_CONTROL_BASE      0x400FD000
#define FLASH_FMA       (FLASH_CONTROL_BASE | 0x000)
#define FLASH_FMD       (FLASH_CONTROL_BASE | 0x004)
#define FLASH_FMC       (FLASH_CONTROL_BASE | 0x008)
#define FLASH_CRIS      (FLASH_CONTROL_BASE | 0x00C)
#define FLASH_CIM       (FLASH_CONTROL_BASE | 0x010)
#define FLASH_MISC      (FLASH_CONTROL_BASE | 0x014)

#define AMISC   1
#define PMISC   2

#define AMASK   1
#define PMASK   2

/* Flash Controller Command bits */
#define FMC_WRKEY       (0xA442 << 16)
#define FMC_COMT        (1 << 3)
#define FMC_MERASE      (1 << 2)
#define FMC_ERASE       (1 << 1)
#define FMC_WRITE       (1 << 0)

/* STELLARIS constants */

/* values to write in FMA to commit write-"once" values */
#define FLASH_FMA_PRE(x)        (2 * (x))       /* for FMPPREx */
#define FLASH_FMA_PPE(x)        (2 * (x) + 1)   /* for FMPPPEx */


static void stellaris_read_clock_info(struct flash_bank *bank);
static int stellaris_mass_erase(struct flash_bank *bank);

struct stellaris_flash_bank
{
        /* chip id register */
        uint32_t did0;
        uint32_t did1;
        uint32_t dc0;
        uint32_t dc1;

        const char * target_name;

        uint32_t sramsiz;
        uint32_t flshsz;
        /* flash geometry */
        uint32_t num_pages;
        uint32_t pagesize;
        uint32_t pages_in_lockregion;

        /* nv memory bits */
        uint16_t num_lockbits;

        /* main clock status */
        uint32_t rcc;
        uint32_t rcc2;
        uint8_t  mck_valid;
        uint8_t  xtal_mask;
        uint32_t iosc_freq;
        uint32_t mck_freq;
        const char *iosc_desc;
        const char *mck_desc;
};

// Autogenerated by contrib/gen-stellaris-part-header.pl
// From Stellaris Firmware Development Package revision 6734
static struct {
        uint32_t partno;
        const char *partname;
}       StellarisParts[] =
{
        {0x0001,"LM3S101"},
        {0x0002,"LM3S102"},
        {0x0019,"LM3S300"},
        {0x0011,"LM3S301"},
        {0x001A,"LM3S308"},
        {0x0012,"LM3S310"},
        {0x0013,"LM3S315"},
        {0x0014,"LM3S316"},
        {0x0017,"LM3S317"},
        {0x0015,"LM3S328"},
        {0x002A,"LM3S600"},
        {0x0021,"LM3S601"},
        {0x002B,"LM3S608"},
        {0x0022,"LM3S610"},
        {0x0023,"LM3S611"},
        {0x0024,"LM3S612"},
        {0x0025,"LM3S613"},
        {0x0026,"LM3S615"},
        {0x0028,"LM3S617"},
        {0x0029,"LM3S618"},
        {0x0027,"LM3S628"},
        {0x0038,"LM3S800"},
        {0x0031,"LM3S801"},
        {0x0039,"LM3S808"},
        {0x0032,"LM3S811"},
        {0x0033,"LM3S812"},
        {0x0034,"LM3S815"},
        {0x0036,"LM3S817"},
        {0x0037,"LM3S818"},
        {0x0035,"LM3S828"},
        {0x10BF,"LM3S1110"},
        {0x10C3,"LM3S1133"},
        {0x10C5,"LM3S1138"},
        {0x10C1,"LM3S1150"},
        {0x10C4,"LM3S1162"},
        {0x10C2,"LM3S1165"},
        {0x10C6,"LM3S1332"},
        {0x10BC,"LM3S1435"},
        {0x10BA,"LM3S1439"},
        {0x10BB,"LM3S1512"},
        {0x10C7,"LM3S1538"},
        {0x10DB,"LM3S1601"},
        {0x1006,"LM3S1607"},
        {0x10DA,"LM3S1608"},
        {0x10C0,"LM3S1620"},
        {0x1003,"LM3S1625"},
        {0x1004,"LM3S1626"},
        {0x1005,"LM3S1627"},
        {0x10B3,"LM3S1635"},
        {0x10BD,"LM3S1637"},
        {0x10B1,"LM3S1651"},
        {0x10B9,"LM3S1751"},
        {0x1010,"LM3S1776"},
        {0x1016,"LM3S1811"},
        {0x103D,"LM3S1816"},
        {0x10B4,"LM3S1850"},
        {0x10DD,"LM3S1911"},
        {0x10DC,"LM3S1918"},
        {0x10B7,"LM3S1937"},
        {0x10BE,"LM3S1958"},
        {0x10B5,"LM3S1960"},
        {0x10B8,"LM3S1968"},
        {0x100F,"LM3S1J11"},
        {0x103C,"LM3S1J16"},
        {0x100E,"LM3S1N11"},
        {0x103B,"LM3S1N16"},
        {0x10B2,"LM3S1P51"},
        {0x109E,"LM3S1R21"},
        {0x1030,"LM3S1W16"},
        {0x102F,"LM3S1Z16"},
        {0x1051,"LM3S2110"},
        {0x1084,"LM3S2139"},
        {0x1039,"LM3S2276"},
        {0x10A2,"LM3S2410"},
        {0x1059,"LM3S2412"},
        {0x1056,"LM3S2432"},
        {0x105A,"LM3S2533"},
        {0x10E1,"LM3S2601"},
        {0x10E0,"LM3S2608"},
        {0x1033,"LM3S2616"},
        {0x1057,"LM3S2620"},
        {0x1085,"LM3S2637"},
        {0x1053,"LM3S2651"},
        {0x1080,"LM3S2671"},
        {0x1050,"LM3S2678"},
        {0x10A4,"LM3S2730"},
        {0x1052,"LM3S2739"},
        {0x103A,"LM3S2776"},
        {0x106D,"LM3S2793"},
        {0x10E3,"LM3S2911"},
        {0x10E2,"LM3S2918"},
        {0x1054,"LM3S2939"},
        {0x108F,"LM3S2948"},
        {0x1058,"LM3S2950"},
        {0x1055,"LM3S2965"},
        {0x106C,"LM3S2B93"},
        {0x1008,"LM3S3634"},
        {0x1043,"LM3S3651"},
        {0x1044,"LM3S3739"},
        {0x1049,"LM3S3748"},
        {0x1045,"LM3S3749"},
        {0x1042,"LM3S3826"},
        {0x1041,"LM3S3J26"},
        {0x1040,"LM3S3N26"},
        {0x103F,"LM3S3W26"},
        {0x103E,"LM3S3Z26"},
        {0x1081,"LM3S5632"},
        {0x100C,"LM3S5651"},
        {0x108A,"LM3S5652"},
        {0x104D,"LM3S5656"},
        {0x1091,"LM3S5662"},
        {0x1096,"LM3S5732"},
        {0x1097,"LM3S5737"},
        {0x10A0,"LM3S5739"},
        {0x1099,"LM3S5747"},
        {0x10A7,"LM3S5749"},
        {0x109A,"LM3S5752"},
        {0x109C,"LM3S5762"},
        {0x1069,"LM3S5791"},
        {0x100B,"LM3S5951"},
        {0x104E,"LM3S5956"},
        {0x1068,"LM3S5B91"},
        {0x1009,"LM3S5K31"},
        {0x104A,"LM3S5K36"},
        {0x100A,"LM3S5P31"},
        {0x1048,"LM3S5P36"},
        {0x100D,"LM3S5P51"},
        {0x104C,"LM3S5P56"},
        {0x1007,"LM3S5R31"},
        {0x104B,"LM3S5R36"},
        {0x1047,"LM3S5T36"},
        {0x1046,"LM3S5Y36"},
        {0x10A1,"LM3S6100"},
        {0x1074,"LM3S6110"},
        {0x10A5,"LM3S6420"},
        {0x1082,"LM3S6422"},
        {0x1075,"LM3S6432"},
        {0x1076,"LM3S6537"},
        {0x1071,"LM3S6610"},
        {0x10E7,"LM3S6611"},
        {0x10E6,"LM3S6618"},
        {0x1083,"LM3S6633"},
        {0x108B,"LM3S6637"},
        {0x10A3,"LM3S6730"},
        {0x1077,"LM3S6753"},
        {0x10E9,"LM3S6911"},
        {0x10E8,"LM3S6918"},
        {0x1089,"LM3S6938"},
        {0x1072,"LM3S6950"},
        {0x1078,"LM3S6952"},
        {0x1073,"LM3S6965"},
        {0x1064,"LM3S8530"},
        {0x108E,"LM3S8538"},
        {0x1061,"LM3S8630"},
        {0x1063,"LM3S8730"},
        {0x108D,"LM3S8733"},
        {0x1086,"LM3S8738"},
        {0x1065,"LM3S8930"},
        {0x108C,"LM3S8933"},
        {0x1088,"LM3S8938"},
        {0x10A6,"LM3S8962"},
        {0x1062,"LM3S8970"},
        {0x10D7,"LM3S8971"},
        {0x1067,"LM3S9790"},
        {0x106B,"LM3S9792"},
        {0x1020,"LM3S9997"},
        {0x1066,"LM3S9B90"},
        {0x106A,"LM3S9B92"},
        {0x106E,"LM3S9B95"},
        {0x106F,"LM3S9B96"},
        {0x1018,"LM3S9L97"},
        {0,"Unknown part"}
};

static char * StellarisClassname[5] =
{
        "Sandstorm",
        "Fury",
        "Unknown",
        "DustDevil",
        "Tempest"
};

/***************************************************************************
*       openocd command interface                                              *
***************************************************************************/

/* flash_bank stellaris <base> <size> 0 0 <target#>
 */
FLASH_BANK_COMMAND_HANDLER(stellaris_flash_bank_command)
{
        struct stellaris_flash_bank *stellaris_info;

        if (CMD_ARGC < 6)
        {
                LOG_WARNING("incomplete flash_bank stellaris configuration");
                return ERROR_FLASH_BANK_INVALID;
        }

        stellaris_info = calloc(sizeof(struct stellaris_flash_bank), 1);
        bank->base = 0x0;
        bank->driver_priv = stellaris_info;

        stellaris_info->target_name = "Unknown target";

        /* part wasn't probed for info yet */
        stellaris_info->did1 = 0;

        /* TODO Specify the main crystal speed in kHz using an optional
         * argument; ditto, the speed of an external oscillator used
         * instead of a crystal.  Avoid programming flash using IOSC.
         */
        return ERROR_OK;
}

static int get_stellaris_info(struct flash_bank *bank, char *buf, int buf_size)
{
        int printed, device_class;
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;

        if (stellaris_info->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        /* Read main and master clock freqency register */
        stellaris_read_clock_info(bank);

        if (DID0_VER(stellaris_info->did0) > 0)
        {
                device_class = (stellaris_info->did0 >> 16) & 0xFF;
        }
        else
        {
                device_class = 0;
        }
        printed = snprintf(buf,
                           buf_size,
                           "\nTI/LMI Stellaris information: Chip is "
                           "class %i (%s) %s rev %c%i\n",
                           device_class,
                           StellarisClassname[device_class],
                           stellaris_info->target_name,
                           (int)('A' + ((stellaris_info->did0 >> 8) & 0xFF)),
                           (int)((stellaris_info->did0) & 0xFF));
        buf += printed;
        buf_size -= printed;

        printed = snprintf(buf,
                           buf_size,
                           "did1: 0x%8.8" PRIx32 ", arch: 0x%4.4" PRIx32
                           ", eproc: %s, ramsize: %ik, flashsize: %ik\n",
                           stellaris_info->did1,
                           stellaris_info->did1,
                           "ARMv7M",
                           (int)((1 + ((stellaris_info->dc0 >> 16) & 0xFFFF))/4),
                           (int)((1 + (stellaris_info->dc0 & 0xFFFF))*2));
        buf += printed;
        buf_size -= printed;

        printed = snprintf(buf,
                           buf_size,
                           "master clock: %ikHz%s, "
                           "rcc is 0x%" PRIx32 ", rcc2 is 0x%" PRIx32 "\n",
                           (int)(stellaris_info->mck_freq / 1000),
                           stellaris_info->mck_desc,
                           stellaris_info->rcc,
                           stellaris_info->rcc2);
        buf += printed;
        buf_size -= printed;

        if (stellaris_info->num_lockbits > 0)
        {
                printed = snprintf(buf,
                                buf_size,
                                "pagesize: %" PRIi32 ", pages: %d, "
                                "lockbits: %i, pages per lockbit: %i\n",
                                stellaris_info->pagesize,
                                (unsigned) stellaris_info->num_pages,
                                stellaris_info->num_lockbits,
                                (unsigned) stellaris_info->pages_in_lockregion);
                buf += printed;
                buf_size -= printed;
        }
        return ERROR_OK;
}

/***************************************************************************
*       chip identification and status                                         *
***************************************************************************/

/* Set the flash timimg register to match current clocking */
static void stellaris_set_flash_timing(struct flash_bank *bank)
{
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;
        uint32_t usecrl = (stellaris_info->mck_freq/1000000ul-1);

        LOG_DEBUG("usecrl = %i",(int)(usecrl));
        target_write_u32(target, SCB_BASE | USECRL, usecrl);
}

static const unsigned rcc_xtal[32] = {
        [0x00] = 1000000,               /* no pll */
        [0x01] = 1843200,               /* no pll */
        [0x02] = 2000000,               /* no pll */
        [0x03] = 2457600,               /* no pll */

        [0x04] = 3579545,
        [0x05] = 3686400,
        [0x06] = 4000000,               /* usb */
        [0x07] = 4096000,

        [0x08] = 4915200,
        [0x09] = 5000000,               /* usb */
        [0x0a] = 5120000,
        [0x0b] = 6000000,               /* (reset) usb */

        [0x0c] = 6144000,
        [0x0d] = 7372800,
        [0x0e] = 8000000,               /* usb */
        [0x0f] = 8192000,

        /* parts before DustDevil use just 4 bits for xtal spec */

        [0x10] = 10000000,              /* usb */
        [0x11] = 12000000,              /* usb */
        [0x12] = 12288000,
        [0x13] = 13560000,

        [0x14] = 14318180,
        [0x15] = 16000000,              /* usb */
        [0x16] = 16384000,
};

/** Read clock configuration and set stellaris_info->usec_clocks. */
static void stellaris_read_clock_info(struct flash_bank *bank)
{
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;
        uint32_t rcc, rcc2, pllcfg, sysdiv, usesysdiv, bypass, oscsrc;
        unsigned xtal;
        unsigned long mainfreq;

        target_read_u32(target, SCB_BASE | RCC, &rcc);
        LOG_DEBUG("Stellaris RCC %" PRIx32 "", rcc);

        target_read_u32(target, SCB_BASE | RCC2, &rcc2);
        LOG_DEBUG("Stellaris RCC2 %" PRIx32 "", rcc);

        target_read_u32(target, SCB_BASE | PLLCFG, &pllcfg);
        LOG_DEBUG("Stellaris PLLCFG %" PRIx32 "", pllcfg);

        stellaris_info->rcc = rcc;
        stellaris_info->rcc = rcc2;

        sysdiv = (rcc >> 23) & 0xF;
        usesysdiv = (rcc >> 22) & 0x1;
        bypass = (rcc >> 11) & 0x1;
        oscsrc = (rcc >> 4) & 0x3;
        xtal = (rcc >> 6) & stellaris_info->xtal_mask;

        /* NOTE: post-Sandstorm parts have RCC2 which may override
         * parts of RCC ... with more sysdiv options, option for
         * 32768 Hz mainfreq, PLL controls.  On Sandstorm it reads
         * as zero, so the "use RCC2" flag is always clear.
         */
        if (rcc2 & (1 << 31)) {
                sysdiv = (rcc2 >> 23) & 0x3F;
                bypass = (rcc2 >> 11) & 0x1;
                oscsrc = (rcc2 >> 4) & 0x7;

                /* FIXME Tempest parts have an additional lsb for
                 * fractional sysdiv (200 MHz / 2.5 == 80 MHz)
                 */
        }

        stellaris_info->mck_desc = "";

        switch (oscsrc)
        {
                case 0:                         /* MOSC */
                        mainfreq = rcc_xtal[xtal];
                        break;
                case 1:                         /* IOSC */
                        mainfreq = stellaris_info->iosc_freq;
                        stellaris_info->mck_desc = stellaris_info->iosc_desc;
                        break;
                case 2:                         /* IOSC/4 */
                        mainfreq = stellaris_info->iosc_freq / 4;
                        stellaris_info->mck_desc = stellaris_info->iosc_desc;
                        break;
                case 3:                         /* lowspeed */
                        /* Sandstorm doesn't have this 30K +/- 30% osc */
                        mainfreq = 30000;
                        stellaris_info->mck_desc = " (±30%)";
                        break;
                case 8:                         /* hibernation osc */
                        /* not all parts support hibernation */
                        mainfreq = 32768;
                        break;

                default: /* NOTREACHED */
                        mainfreq = 0;
                        break;
        }

        /* PLL is used if it's not bypassed; its output is 200 MHz
         * even when it runs at 400 MHz (adds divide-by-two stage).
         */
        if (!bypass)
                mainfreq = 200000000;

        if (usesysdiv)
                stellaris_info->mck_freq = mainfreq/(1 + sysdiv);
        else
                stellaris_info->mck_freq = mainfreq;
}

/* Read device id register, main clock frequency register and fill in driver info structure */
static int stellaris_read_part_info(struct flash_bank *bank)
{
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;
        uint32_t did0, did1, ver, fam;
        int i;

        /* Read and parse chip identification register */
        target_read_u32(target, SCB_BASE | DID0, &did0);
        target_read_u32(target, SCB_BASE | DID1, &did1);
        target_read_u32(target, SCB_BASE | DC0, &stellaris_info->dc0);
        target_read_u32(target, SCB_BASE | DC1, &stellaris_info->dc1);
        LOG_DEBUG("did0 0x%" PRIx32 ", did1 0x%" PRIx32 ", dc0 0x%" PRIx32 ", dc1 0x%" PRIx32 "",
                  did0, did1, stellaris_info->dc0, stellaris_info->dc1);

        ver = did0 >> 28;
        if ((ver != 0) && (ver != 1))
        {
                LOG_WARNING("Unknown did0 version, cannot identify target");
                return ERROR_FLASH_OPERATION_FAILED;
        }

        if (did1 == 0)
        {
                LOG_WARNING("Cannot identify target as a Stellaris");
                return ERROR_FLASH_OPERATION_FAILED;
        }

        ver = did1 >> 28;
        fam = (did1 >> 24) & 0xF;
        if (((ver != 0) && (ver != 1)) || (fam != 0))
        {
                LOG_WARNING("Unknown did1 version/family.");
                return ERROR_FLASH_OPERATION_FAILED;
        }

        /* For Sandstorm, Fury, DustDevil:  current data sheets say IOSC
         * is 12 MHz, but some older parts have 15 MHz.  A few data sheets
         * even give _both_ numbers!  We'll use current numbers; IOSC is
         * always approximate.
         *
         * For Tempest:  IOSC is calibrated, 16 MHz
         */
        stellaris_info->iosc_freq = 12000000;
        stellaris_info->iosc_desc = " (±30%)";
        stellaris_info->xtal_mask = 0x0f;

        switch ((did0 >> 28) & 0x7) {
        case 0:                         /* Sandstorm */
                /*
                 * Current (2009-August) parts seem to be rev C2 and use 12 MHz.
                 * Parts before rev C0 used 15 MHz; some C0 parts use 15 MHz
                 * (LM3S618), but some other C0 parts are 12 MHz (LM3S811).
                 */
                if (((did0 >> 8) & 0xff) < 2) {
                        stellaris_info->iosc_freq = 15000000;
                        stellaris_info->iosc_desc = " (±50%)";
                }
                break;
        case 1:
                switch ((did0 >> 16) & 0xff) {
                case 1:                 /* Fury */
                        break;
                case 4:                 /* Tempest */
                        stellaris_info->iosc_freq = 16000000;   /* +/- 1% */
                        stellaris_info->iosc_desc = " (±1%)";
                        /* FALL THROUGH */
                case 3:                 /* DustDevil */
                        stellaris_info->xtal_mask = 0x1f;
                        break;
                default:
                        LOG_WARNING("Unknown did0 class");
                }
                break;
        default:
                LOG_WARNING("Unknown did0 version");
                break;
        }

        for (i = 0; StellarisParts[i].partno; i++)
        {
                if (StellarisParts[i].partno == ((did1 >> 16) & 0xFFFF))
                        break;
        }

        stellaris_info->target_name = StellarisParts[i].partname;

        stellaris_info->did0 = did0;
        stellaris_info->did1 = did1;

        stellaris_info->num_lockbits = 1 + (stellaris_info->dc0 & 0xFFFF);
        stellaris_info->num_pages = 2 *(1 + (stellaris_info->dc0 & 0xFFFF));
        stellaris_info->pagesize = 1024;
        stellaris_info->pages_in_lockregion = 2;

        /* REVISIT for at least Tempest parts, read NVMSTAT.FWB too.
         * That exposes a 32-word Flash Write Buffer ... enabling
         * writes of more than one word at a time.
         */

        return ERROR_OK;
}

/***************************************************************************
*       flash operations                                                       *
***************************************************************************/

static int stellaris_protect_check(struct flash_bank *bank)
{
        struct stellaris_flash_bank *stellaris = bank->driver_priv;
        int status = ERROR_OK;
        unsigned i;
        unsigned page;

        if (stellaris->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        for (i = 0; i < (unsigned) bank->num_sectors; i++)
                bank->sectors[i].is_protected = -1;

        /* Read each Flash Memory Protection Program Enable (FMPPE) register
         * to report any pages that we can't write.  Ignore the Read Enable
         * register (FMPRE).
         */
        for (i = 0, page = 0;
                        i < DIV_ROUND_UP(stellaris->num_lockbits, 32u);
                        i++) {
                uint32_t lockbits;

                status = target_read_u32(bank->target,
                                SCB_BASE + (i ? (FMPPE0 + 4 * i) : FMPPE),
                                &lockbits);
                LOG_DEBUG("FMPPE%d = %#8.8x (status %d)", i,
                                (unsigned) lockbits, status);
                if (status != ERROR_OK)
                        goto done;

                for (unsigned j = 0; j < 32; j++) {
                        unsigned k;

                        for (k = 0; k < stellaris->pages_in_lockregion; k++) {
                                if (page >= (unsigned) bank->num_sectors)
                                        goto done;
                                bank->sectors[page++].is_protected =
                                                !(lockbits & (1 << j));
                        }
                }
        }

done:
        return status;
}

static int stellaris_erase(struct flash_bank *bank, int first, int last)
{
        int banknr;
        uint32_t flash_fmc, flash_cris;
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;

        if (bank->target->state != TARGET_HALTED)
        {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        if (stellaris_info->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        if ((first < 0) || (last < first) || (last >= (int)stellaris_info->num_pages))
        {
                return ERROR_FLASH_SECTOR_INVALID;
        }

        if ((first == 0) && (last == ((int)stellaris_info->num_pages-1)))
        {
                return stellaris_mass_erase(bank);
        }

        /* Refresh flash controller timing */
        stellaris_read_clock_info(bank);
        stellaris_set_flash_timing(bank);

        /* Clear and disable flash programming interrupts */
        target_write_u32(target, FLASH_CIM, 0);
        target_write_u32(target, FLASH_MISC, PMISC | AMISC);

        /* REVISIT this clobbers state set by any halted firmware ...
         * it might want to process those IRQs.
         */

        for (banknr = first; banknr <= last; banknr++)
        {
                /* Address is first word in page */
                target_write_u32(target, FLASH_FMA, banknr * stellaris_info->pagesize);
                /* Write erase command */
                target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_ERASE);
                /* Wait until erase complete */
                do
                {
                        target_read_u32(target, FLASH_FMC, &flash_fmc);
                }
                while (flash_fmc & FMC_ERASE);

                /* Check acess violations */
                target_read_u32(target, FLASH_CRIS, &flash_cris);
                if (flash_cris & (AMASK))
                {
                        LOG_WARNING("Error erasing flash page %i,  flash_cris 0x%" PRIx32 "", banknr, flash_cris);
                        target_write_u32(target, FLASH_CRIS, 0);
                        return ERROR_FLASH_OPERATION_FAILED;
                }

                bank->sectors[banknr].is_erased = 1;
        }

        return ERROR_OK;
}

static int stellaris_protect(struct flash_bank *bank, int set, int first, int last)
{
        uint32_t fmppe, flash_fmc, flash_cris;
        int lockregion;

        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;

        if (bank->target->state != TARGET_HALTED)
        {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        if (!set)
        {
                LOG_ERROR("Hardware doesn't suppport page-level unprotect. "
                        "Try the 'recover' command.");
                return ERROR_INVALID_ARGUMENTS;
        }

        if (stellaris_info->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        /* lockregions are 2 pages ... must protect [even..odd] */
        if ((first < 0) || (first & 1)
                        || (last < first) || !(last & 1)
                        || (last >= 2 * stellaris_info->num_lockbits))
        {
                LOG_ERROR("Can't protect unaligned or out-of-range pages.");
                return ERROR_FLASH_SECTOR_INVALID;
        }

        /* Refresh flash controller timing */
        stellaris_read_clock_info(bank);
        stellaris_set_flash_timing(bank);

        /* convert from pages to lockregions */
        first /= 2;
        last /= 2;

        /* FIXME this assumes single FMPPE, for a max of 64K of flash!!
         * Current parts can be much bigger.
         */
        if (last >= 32) {
                LOG_ERROR("No support yet for protection > 64K");
                return ERROR_FLASH_OPERATION_FAILED;
        }

        target_read_u32(target, SCB_BASE | FMPPE, &fmppe);

        for (lockregion = first; lockregion <= last; lockregion++)
                fmppe &= ~(1 << lockregion);

        /* Clear and disable flash programming interrupts */
        target_write_u32(target, FLASH_CIM, 0);
        target_write_u32(target, FLASH_MISC, PMISC | AMISC);

        /* REVISIT this clobbers state set by any halted firmware ...
         * it might want to process those IRQs.
         */

        LOG_DEBUG("fmppe 0x%" PRIx32 "",fmppe);
        target_write_u32(target, SCB_BASE | FMPPE, fmppe);

        /* Commit FMPPE */
        target_write_u32(target, FLASH_FMA, 1);

        /* Write commit command */
        /* REVISIT safety check, since this cannot be undone
         * except by the "Recover a locked device" procedure.
         * REVISIT DustDevil-A0 parts have an erratum making FMPPE commits
         * inadvisable ... it makes future mass erase operations fail.
         */
        LOG_WARNING("Flash protection cannot be removed once commited, commit is NOT executed !");
        /* target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_COMT); */

        /* Wait until erase complete */
        do
        {
                target_read_u32(target, FLASH_FMC, &flash_fmc);
        }
        while (flash_fmc & FMC_COMT);

        /* Check acess violations */
        target_read_u32(target, FLASH_CRIS, &flash_cris);
        if (flash_cris & (AMASK))
        {
                LOG_WARNING("Error setting flash page protection,  flash_cris 0x%" PRIx32 "", flash_cris);
                target_write_u32(target, FLASH_CRIS, 0);
                return ERROR_FLASH_OPERATION_FAILED;
        }

        return ERROR_OK;
}

/* see contib/loaders/flash/stellaris.s for src */

static const uint8_t stellaris_write_code[] =
{
/*
        Call with :
        r0 = buffer address
        r1 = destination address
        r2 = bytecount (in) - endaddr (work)

        Used registers:
        r3 = pFLASH_CTRL_BASE
        r4 = FLASHWRITECMD
        r5 = #1
        r6 = bytes written
        r7 = temp reg
*/
        0x07,0x4B,                      /* ldr r3,pFLASH_CTRL_BASE */
        0x08,0x4C,                      /* ldr r4,FLASHWRITECMD */
        0x01,0x25,                      /* movs r5, 1 */
        0x00,0x26,                      /* movs r6, #0 */
/* mainloop: */
        0x19,0x60,                      /* str  r1, [r3, #0] */
        0x87,0x59,                      /* ldr  r7, [r0, r6] */
        0x5F,0x60,                      /* str  r7, [r3, #4] */
        0x9C,0x60,                      /* str  r4, [r3, #8] */
/* waitloop: */
        0x9F,0x68,                      /* ldr  r7, [r3, #8] */
        0x2F,0x42,                      /* tst  r7, r5 */
        0xFC,0xD1,                      /* bne  waitloop */
        0x04,0x31,                      /* adds r1, r1, #4 */
        0x04,0x36,                      /* adds r6, r6, #4 */
        0x96,0x42,                      /* cmp  r6, r2 */
        0xF4,0xD1,                      /* bne  mainloop */
        0x00,0xBE,              /* bkpt #0 */
/* pFLASH_CTRL_BASE: */
        0x00,0xD0,0x0F,0x40,    /* .word        0x400FD000 */
/* FLASHWRITECMD: */
        0x01,0x00,0x42,0xA4     /* .word        0xA4420001 */
};

static int stellaris_write_block(struct flash_bank *bank,
                uint8_t *buffer, uint32_t offset, uint32_t wcount)
{
        struct target *target = bank->target;
        uint32_t buffer_size = 16384;
        struct working_area *source;
        struct working_area *write_algorithm;
        uint32_t address = bank->base + offset;
        struct reg_param reg_params[3];
        struct armv7m_algorithm armv7m_info;
        int retval = ERROR_OK;

        /* power of two, and multiple of word size */
        static const unsigned buf_min = 128;

        /* for small buffers it's faster not to download an algorithm */
        if (wcount * 4 < buf_min)
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;

        LOG_DEBUG("(bank=%p buffer=%p offset=%08" PRIx32 " wcount=%08" PRIx32 "",
                        bank, buffer, offset, wcount);

        /* flash write code */
        if (target_alloc_working_area(target, sizeof(stellaris_write_code), &write_algorithm) != ERROR_OK)
        {
                LOG_DEBUG("no working area for block memory writes");
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        };

        /* plus a buffer big enough for this data */
        if (wcount * 4 < buffer_size)
                buffer_size = wcount * 4;

        /* memory buffer */
        while (target_alloc_working_area_try(target, buffer_size, &source) != ERROR_OK)
        {
                buffer_size /= 2;
                if (buffer_size <= buf_min)
                {
                        target_free_working_area(target, write_algorithm);
                        return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
                }
                LOG_DEBUG("retry target_alloc_working_area(%s, size=%u)",
                                target_name(target), (unsigned) buffer_size);
        };

        retval = target_write_buffer(target, write_algorithm->address,
                        sizeof(stellaris_write_code),
                        (uint8_t *) stellaris_write_code);

        armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
        armv7m_info.core_mode = ARMV7M_MODE_ANY;

        init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
        init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
        init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);

        while (wcount > 0)
        {
                uint32_t thisrun_count = (wcount > (buffer_size / 4)) ? (buffer_size / 4) : wcount;

                target_write_buffer(target, source->address, thisrun_count * 4, buffer);

                buf_set_u32(reg_params[0].value, 0, 32, source->address);
                buf_set_u32(reg_params[1].value, 0, 32, address);
                buf_set_u32(reg_params[2].value, 0, 32, 4*thisrun_count);
                LOG_DEBUG("Algorithm flash write %u words to 0x%" PRIx32
                                ", %u remaining",
                                (unsigned) thisrun_count, address,
                                (unsigned) (wcount - thisrun_count));
                retval = target_run_algorithm(target, 0, NULL, 3, reg_params,
                                write_algorithm->address,
                                0,
                                10000, &armv7m_info);
                if (retval != ERROR_OK)
                {
                        LOG_ERROR("error %d executing stellaris "
                                        "flash write algorithm",
                                        retval);
                        retval = ERROR_FLASH_OPERATION_FAILED;
                        break;
                }

                buffer += thisrun_count * 4;
                address += thisrun_count * 4;
                wcount -= thisrun_count;
        }

        /* REVISIT we could speed up writing multi-section images by
         * not freeing the initialized write_algorithm this way.
         */

        target_free_working_area(target, write_algorithm);
        target_free_working_area(target, source);

        destroy_reg_param(&reg_params[0]);
        destroy_reg_param(&reg_params[1]);
        destroy_reg_param(&reg_params[2]);

        return retval;
}

static int stellaris_write(struct flash_bank *bank, uint8_t *buffer, uint32_t offset, uint32_t count)
{
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        struct target *target = bank->target;
        uint32_t address = offset;
        uint32_t flash_cris, flash_fmc;
        uint32_t words_remaining = (count / 4);
        uint32_t bytes_remaining = (count & 0x00000003);
        uint32_t bytes_written = 0;
        int retval;

        if (bank->target->state != TARGET_HALTED)
        {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        LOG_DEBUG("(bank=%p buffer=%p offset=%08" PRIx32 " count=%08" PRIx32 "",
                        bank, buffer, offset, count);

        if (stellaris_info->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        if (offset & 0x3)
        {
                LOG_WARNING("offset size must be word aligned");
                return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
        }

        if (offset + count > bank->size)
                return ERROR_FLASH_DST_OUT_OF_BANK;

        /* Refresh flash controller timing */
        stellaris_read_clock_info(bank);
        stellaris_set_flash_timing(bank);

        /* Clear and disable flash programming interrupts */
        target_write_u32(target, FLASH_CIM, 0);
        target_write_u32(target, FLASH_MISC, PMISC | AMISC);

        /* REVISIT this clobbers state set by any halted firmware ...
         * it might want to process those IRQs.
         */

        /* multiple words to be programmed? */
        if (words_remaining > 0)
        {
                /* try using a block write */
                retval = stellaris_write_block(bank, buffer, offset,
                                words_remaining);
                if (retval != ERROR_OK)
                {
                        if (retval == ERROR_TARGET_RESOURCE_NOT_AVAILABLE)
                        {
                                LOG_DEBUG("writing flash word-at-a-time");
                        }
                        else if (retval == ERROR_FLASH_OPERATION_FAILED)
                        {
                                /* if an error occured, we examine the reason, and quit */
                                target_read_u32(target, FLASH_CRIS, &flash_cris);

                                LOG_ERROR("flash writing failed with CRIS: 0x%" PRIx32 "", flash_cris);
                                return ERROR_FLASH_OPERATION_FAILED;
                        }
                }
                else
                {
                        buffer += words_remaining * 4;
                        address += words_remaining * 4;
                        words_remaining = 0;
                }
        }

        while (words_remaining > 0)
        {
                if (!(address & 0xff))
                        LOG_DEBUG("0x%" PRIx32 "", address);

                /* Program one word */
                target_write_u32(target, FLASH_FMA, address);
                target_write_buffer(target, FLASH_FMD, 4, buffer);
                target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_WRITE);
                /* LOG_DEBUG("0x%x 0x%x 0x%x",address,buf_get_u32(buffer, 0, 32),FMC_WRKEY | FMC_WRITE); */
                /* Wait until write complete */
                do
                {
                        target_read_u32(target, FLASH_FMC, &flash_fmc);
                } while (flash_fmc & FMC_WRITE);

                buffer += 4;
                address += 4;
                words_remaining--;
        }

        if (bytes_remaining)
        {
                uint8_t last_word[4] = {0xff, 0xff, 0xff, 0xff};
                int i = 0;

                while (bytes_remaining > 0)
                {
                        last_word[i++] = *(buffer + bytes_written);
                        bytes_remaining--;
                        bytes_written++;
                }

                if (!(address & 0xff))
                        LOG_DEBUG("0x%" PRIx32 "", address);

                /* Program one word */
                target_write_u32(target, FLASH_FMA, address);
                target_write_buffer(target, FLASH_FMD, 4, last_word);
                target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_WRITE);
                /* LOG_DEBUG("0x%x 0x%x 0x%x",address,buf_get_u32(buffer, 0, 32),FMC_WRKEY | FMC_WRITE); */
                /* Wait until write complete */
                do
                {
                        target_read_u32(target, FLASH_FMC, &flash_fmc);
                } while (flash_fmc & FMC_WRITE);
        }

        /* Check access violations */
        target_read_u32(target, FLASH_CRIS, &flash_cris);
        if (flash_cris & (AMASK))
        {
                LOG_DEBUG("flash_cris 0x%" PRIx32 "", flash_cris);
                return ERROR_FLASH_OPERATION_FAILED;
        }
        return ERROR_OK;
}

static int stellaris_probe(struct flash_bank *bank)
{
        struct stellaris_flash_bank *stellaris_info = bank->driver_priv;
        int retval;

        /* If this is a stellaris chip, it has flash; probe() is just
         * to figure out how much is present.  Only do it once.
         */
        if (stellaris_info->did1 != 0)
                return ERROR_OK;

        /* stellaris_read_part_info() already handled error checking and
         * reporting.  Note that it doesn't write, so we don't care about
         * whether the target is halted or not.
         */
        retval = stellaris_read_part_info(bank);
        if (retval != ERROR_OK)
                return retval;

        if (bank->sectors)
        {
                free(bank->sectors);
                bank->sectors = NULL;
        }

        /* provide this for the benefit of the NOR flash framework */
        bank->size = 1024 * stellaris_info->num_pages;
        bank->num_sectors = stellaris_info->num_pages;
        bank->sectors = calloc(bank->num_sectors, sizeof(struct flash_sector));
        for (int i = 0; i < bank->num_sectors; i++)
        {
                bank->sectors[i].offset = i * stellaris_info->pagesize;
                bank->sectors[i].size = stellaris_info->pagesize;
                bank->sectors[i].is_erased = -1;
                bank->sectors[i].is_protected = -1;
        }

        return retval;
}

static int stellaris_mass_erase(struct flash_bank *bank)
{
        struct target *target = NULL;
        struct stellaris_flash_bank *stellaris_info = NULL;
        uint32_t flash_fmc;

        stellaris_info = bank->driver_priv;
        target = bank->target;

        if (target->state != TARGET_HALTED)
        {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        if (stellaris_info->did1 == 0)
                return ERROR_FLASH_BANK_NOT_PROBED;

        /* Refresh flash controller timing */
        stellaris_read_clock_info(bank);
        stellaris_set_flash_timing(bank);

        /* Clear and disable flash programming interrupts */
        target_write_u32(target, FLASH_CIM, 0);
        target_write_u32(target, FLASH_MISC, PMISC | AMISC);

        /* REVISIT this clobbers state set by any halted firmware ...
         * it might want to process those IRQs.
         */

        target_write_u32(target, FLASH_FMA, 0);
        target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_MERASE);
        /* Wait until erase complete */
        do
        {
                target_read_u32(target, FLASH_FMC, &flash_fmc);
        }
        while (flash_fmc & FMC_MERASE);

        /* if device has > 128k, then second erase cycle is needed
         * this is only valid for older devices, but will not hurt */
        if (stellaris_info->num_pages * stellaris_info->pagesize > 0x20000)
        {
                target_write_u32(target, FLASH_FMA, 0x20000);
                target_write_u32(target, FLASH_FMC, FMC_WRKEY | FMC_MERASE);
                /* Wait until erase complete */
                do
                {
                        target_read_u32(target, FLASH_FMC, &flash_fmc);
                }
                while (flash_fmc & FMC_MERASE);
        }

        return ERROR_OK;
}

COMMAND_HANDLER(stellaris_handle_mass_erase_command)
{
        int i;

        if (CMD_ARGC < 1)
        {
                command_print(CMD_CTX, "stellaris mass_erase <bank>");
                return ERROR_OK;
        }

        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
        if (ERROR_OK != retval)
                return retval;

        if (stellaris_mass_erase(bank) == ERROR_OK)
        {
                /* set all sectors as erased */
                for (i = 0; i < bank->num_sectors; i++)
                {
                        bank->sectors[i].is_erased = 1;
                }

                command_print(CMD_CTX, "stellaris mass erase complete");
        }
        else
        {
                command_print(CMD_CTX, "stellaris mass erase failed");
        }

        return ERROR_OK;
}

/**
 * Perform the Stellaris "Recovering a 'Locked' Device procedure.
 * This performs a mass erase and then restores all nonvolatile registers
 * (including USER_* registers and flash lock bits) to their defaults.
 * Accordingly, flash can be reprogrammed, and JTAG can be used.
 *
 * NOTE that DustDevil parts (at least rev A0 silicon) have errata which
 * can affect this operation if flash protection has been enabled.
 */
COMMAND_HANDLER(stellaris_handle_recover_command)
{
        struct flash_bank *bank;
        int retval;

        retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
        if (retval != ERROR_OK)
                return retval;

        /* REVISIT ... it may be worth sanity checking that the AP is
         * inactive before we start.  ARM documents that switching a DP's
         * mode while it's active can cause fault modes that need a power
         * cycle to recover.
         */

        /* assert SRST */
        if (!(jtag_get_reset_config() & RESET_HAS_SRST)) {
                LOG_ERROR("Can't recover Stellaris flash without SRST");
                return ERROR_FAIL;
        }
        jtag_add_reset(0, 1);

        for (int i = 0; i < 5; i++) {
                retval = dap_to_swd(bank->target);
                if (retval != ERROR_OK)
                        goto done;

                retval = dap_to_jtag(bank->target);
                if (retval != ERROR_OK)
                        goto done;
        }

        /* de-assert SRST */
        jtag_add_reset(0, 0);
        retval = jtag_execute_queue();

        /* wait 400+ msec ... OK, "1+ second" is simpler */
        usleep(1000);

        /* USER INTERVENTION required for the power cycle
         * Restarting OpenOCD is likely needed because of mode switching.
         */
        LOG_INFO("USER ACTION:  "
                "power cycle Stellaris chip, then restart OpenOCD.");

done:
        return retval;
}

static const struct command_registration stellaris_exec_command_handlers[] = {
        {
                .name = "mass_erase",
                .handler = stellaris_handle_mass_erase_command,
                .mode = COMMAND_EXEC,
                .usage = "bank_id",
                .help = "erase entire device",
        },
        {
                .name = "recover",
                .handler = stellaris_handle_recover_command,
                .mode = COMMAND_EXEC,
                .usage = "bank_id",
                .help = "recover (and erase) locked device",
        },
        COMMAND_REGISTRATION_DONE
};
static const struct command_registration stellaris_command_handlers[] = {
        {
                .name = "stellaris",
                .mode = COMMAND_EXEC,
                .help = "Stellaris flash command group",
                .chain = stellaris_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

struct flash_driver stellaris_flash = {
        .name = "stellaris",
        .commands = stellaris_command_handlers,
        .flash_bank_command = stellaris_flash_bank_command,
        .erase = stellaris_erase,
        .protect = stellaris_protect,
        .write = stellaris_write,
        .read = default_flash_read,
        .probe = stellaris_probe,
        .auto_probe = stellaris_probe,
        .erase_check = default_flash_mem_blank_check,
        .protect_check = stellaris_protect_check,
        .info = get_stellaris_info,
};